Sofa



FIG. 1 is a front perspective view of a sofa showing my design;

FIG. 2 is a perspective view thereof;

FIG. 3 is a rear perspective view thereof; and

FIG. 4 is a top view thereof.

FIG. 5 is a front perspective view of a second embodiment of my design;

FIG. 6 is a rear perspective view thereof;

FIG. 7 is a side perspective view thereof; and

FIG. 8 is a top view thereof.

The ornamental design for a sofa, as shown and described.